--  @testpoint:opengauss关键字bigint(非保留)，作为函数名
--关键字不带引号-合理报错
drop function if exists bigint;
create function bigint(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--关键字带双引号-成功
drop function if exists "bigint";
create function "bigint"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function "bigint";

--关键字带单引号-合理报错
drop function if exists 'bigint';
create function 'bigint'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/

--关键字带反引号-合理报错
drop function if exists `bigint`;
create function `bigint`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/